The invention concerns a method for regulating a conveying stream composed of articles of the tobacco-processing industry between at least one tray discharger and at least one feed device connected to the or each tray discharger by a conveying element for conveying a mass flow consisting of articles, wherein the feed device has at least one chamber designed to receive the articles, and each chamber has at least two feed units running independently of each other for feeding the articles to subsequent apparatuses, wherein each feed unit has an individual feed rate (P1, P2, . . . Pn), with the steps of: monitoring the level within the feed device using monitoring elements, sending a signal to each tray discharger for regulating the speed of transport of the conveying element and hence the feed rate (in articles/min) dependent on the current level within the feed device, and adapting the speed of transport to the desired level. Furthermore the invention concerns an arrangement for transferring rod-shaped articles of the tobacco-processing industry to subsequent apparatuses, comprising at least one tray discharger, at least one feed device, wherein the feed device has at least one chamber designed to receive the articles and each chamber being assigned at least two feed units, each tray discharger and the feed device being connected to each other by a conveying element and each comprising a control system for regulating the conveying element.
Such methods and apparatuses are used in particular in the tobacco-processing industry. Here, preferably rod-shaped articles such as e.g. filter rods or the like are processed. In particular, these articles are frequently stocked or temporarily stored in containers, the so-called trays, or otherwise. The articles delivered to the feed device are then sent from the latter preferably pneumatically to subsequent apparatuses. For this purpose the feed device has at least two, but preferably more feed units, by means of which the articles are sent dependent on the individual feed rate. In order now to supply this feed device with articles, the articles are transferred from the trays or the like to the tray discharger, and from the tray discharger via the conveying element the mass flow composed of the articles is transported to the feed device. The mass flow flows in the region of an inlet into the magazine of the feed device. The monitoring elements, which are preferably arranged within the magazine, detect the current level within the magazine. With the aid of the information picked up by the monitoring elements, the speed of transport of the conveying element and hence the feed rate of articles are regulated.
In practice, this means that the signal exchange is usually effected via two signals by means of which only three different states for the conveying element can be shown, namely e.g. a) transport no articles, b) transport 100% articles and c) transport more than 100% articles. This method, however, has the drawback that only uneven supply of the magazine of the feed device with a varying level within the magazine can be achieved. In other words, the magazine of the feed device is supplied with articles cyclically only, wherein filling of the magazine depends exclusively on the level of the magazine. Switching the conveying element on and off alternately, accompanied by interruption of the stream of articles into the receiving device, leads to so-called stop-and-go operation. Document DE 33 33 859 A1 from the applicant's firm shows a storage arrangement and a corresponding method having the features of the preambles of independent claims 1 and 19. The arrangement shown there has a receiving chamber within the feed device, the level of which is monitored by sensing means. Depending on the information of the sensing means, the input conveyor for the delivery of articles is switched on or off. A comparable arrangement can be found in DE 36 11 707 A1, which also comes from the applicant's firm, wherein the storage container of the feed device has two chambers. An input conveying means leads into each chamber. The articles conducted into the chamber by the respective input conveying means are carried away via outlet shafts assigned to each chamber. From DE 35 38 660 C2 is known a signal transmission system in which delivery of the articles to a receiving device is regulated dependent on the level of the latter device. The feed amount is regulated by interrupting the conveying stream for an interval of time, in order then to be switched on again for an interval of time.